BestNest Cal Pump PW2500 Waterfall Pump and Prefilter, 2650 gph Contains Cal Pump PW2500 and TS1.5 Prefilter This pump features a 0.25 Hp direct drive motor capable of turning 2650 gph at 1'. It accepts a male 1.25", female 1.25", female 1", or female 2" NPT threaded fitting. Install the TS1.5 on the inlet to elevate the pump from any debris on the bottom of the water feature.